U.S. patent application number 17/259524 was filed with the patent office on 2021-08-05 for hydraulic machine.
The applicant listed for this patent is Volvo Construction Equipment AB. Invention is credited to Manseuk Jeon.
Application Number | 20210239141 17/259524 |
Document ID | / |
Family ID | 1000005567433 |
Filed Date | 2021-08-05 |
United States Patent
Application |
20210239141 |
Kind Code |
A1 |
Jeon; Manseuk |
August 5, 2021 |
HYDRAULIC MACHINE
Abstract
In a hydraulic machine, first travel control valve and a first
attachment control valve are in fluid communication with a second
hydraulic source. A confluence control valve is in fluid
communication with a first hydraulic source and, in a confluence
position, directs fluid from the first hydraulic source to the
first attachment control valve. A first signal line and a first
pilot line are connected to the confluence control valve. When the
first travel control valve is in a non-neutral position and the
first attachment control valve is in a first non-neutral position,
first signal pressure is generated in the first signal line to move
the confluence control valve to the confluence position. First
pilot pressure, when generated in the first pilot line, moves the
confluence control valve to the confluence position.
Inventors: |
Jeon; Manseuk;
(Gyeongsangnam-do, KR) |
|
Applicant: |
Name |
City |
State |
Country |
Type |
Volvo Construction Equipment AB |
Eskiistuna |
|
SE |
|
|
Family ID: |
1000005567433 |
Appl. No.: |
17/259524 |
Filed: |
July 12, 2018 |
PCT Filed: |
July 12, 2018 |
PCT NO: |
PCT/KR2018/007894 |
371 Date: |
January 11, 2021 |
Current U.S.
Class: |
1/1 |
Current CPC
Class: |
F15B 13/06 20130101;
E02F 9/2285 20130101 |
International
Class: |
F15B 13/06 20060101
F15B013/06; E02F 9/22 20060101 E02F009/22 |
Claims
1. A hydraulic machine comprising: a first hydraulic source; a
second hydraulic source; a first travel control valve in fluid
communication with the second hydraulic source; a first attachment
control valve in fluid communication with the second hydraulic
source; a confluence control valve in fluid communication with the
first hydraulic source and, in a confluence position, directing
fluid from the first hydraulic source to the first attachment
control valve; a first signal line connected to the confluence
control valve; and a first pilot line connected to the confluence
control valve, wherein, when the first travel control valve is in a
non-neutral position and the first attachment control valve is in a
first non-neutral position, first signal pressure is generated in
the first signal line to move the confluence control valve to the
confluence position, and when first pilot pressure is generated in
the first pilot line, the first pilot pressure moves the confluence
control valve to the confluence position.
2. The hydraulic machine of claim 1, further comprising a second
pilot line connected to the first attachment control valve,
wherein, when second pilot pressure is generated in the second
pilot line, the second pilot pressure moves the first attachment
control valve, and the second pilot line is in fluid communication
with the first pilot line.
3. The hydraulic machine of claim 1, further comprising a first
drain line, wherein, when the first attachment control valve is in
a neutral position, the first signal line is in fluid communication
with the first drain line through the first attachment control
valve.
4. The hydraulic machine of claim 3, wherein, when the first
attachment control valve is in the first non-neutral position, a
flow of fluid from the first signal line to the first drain line is
blocked, and when the first attachment control valve is in a second
non-neutral position, the first signal line is in fluid
communication with the first drain line through the first
attachment control valve.
5. The hydraulic machine of claim 4, wherein, when the first
attachment control valve is in the first non-neutral position, a
flow of fluid from the first drain line to the first signal line is
allowed.
6. The hydraulic machine of claim 4, further comprising a second
pilot line connected to the first attachment control valve,
wherein, when second pilot pressure is generated in the second
pilot line, the second pilot pressure moves the first attachment
control valve to the second non-neutral position, and the second
pilot line is in fluid communication with the first pilot line.
7. The hydraulic machine of claim 1, further comprising an
auxiliary valve, a second signal line, and a second drain line,
wherein, when the auxiliary valve is in an open position, the first
signal line communicates with the second drain line through the
auxiliary valve, and when the first travel control valve is in the
non-neutral position, second signal pressure is generated in the
second signal line to move the auxiliary valve to a closed
position.
8. The hydraulic machine of claim 7, further comprising a third
drain line, wherein, when the first travel control valve is in a
neutral position, the second signal line is in fluid communication
with the third drain line through the first travel control
valve.
9. The hydraulic machine of claim 1, further comprising a fourth
drain line connected to the confluence control valve.
10. The hydraulic machine of claim 1, further comprising a tank and
a tank return line connected to the tank, wherein, when the first
travel control valve is in a neutral position and the first
attachment control valve is in a neutral position, fluid supplied
by the second hydraulic source returns to the tank through the tank
return line after sequentially passing through the first travel
control valve and the first attachment control valve.
11. The hydraulic machine of claim 1, further comprising: a third
hydraulic source; a second travel control valve in fluid
communication with the third hydraulic source; and a second
attachment control valve in fluid communication with the third
hydraulic source.
12. The hydraulic machine of claim 11, further comprising a first
drain line, wherein, when the first attachment control valve and
the second attachment control valve are in neutral positions, fluid
in the first signal line flows to the first drain line through the
first attachment control valve and the second attachment control
valve, and when the first attachment control valve is in the first
non-neutral position and/or the second attachment control valve is
in a third non-neutral position, fluid communication between the
first signal line and the first drain line is blocked.
13. The hydraulic machine of claim 11, further comprising an
auxiliary valve, a second signal line, a second drain line, and a
third drain line, wherein, when the auxiliary valve is in an open
position, the first signal line communicates with the second drain
line through the auxiliary valve, when the first travel control
valve is in a neutral position and the second travel control valve
is in a neutral position, fluid in the second signal line flows to
the third drain line through the first travel control valve and the
second travel control valve, and when the first travel control
valve is in the non-neutral position and/or the second travel
control valve is in a non-neutral position, second signal pressure
is generated in the second signal line to move the auxiliary valve
to a closed position.
14. The hydraulic machine of claim 1, further comprising: a first
drain line; and a third attachment control valve in fluid
communication with the second hydraulic source, wherein, when the
first attachment control valve is in a neutral position and/or the
third attachment control valve is in a neutral position, fluid in
the first signal line flows to the first drain line through the
first attachment control valve and the third attachment control
valve, and when the third attachment control valve is in a
non-neutral position, fluid communication between the first signal
line and the first drain line is blocked.
Description
TECHNICAL FIELD
[0001] The present disclosure relates to a hydraulic machine, and
more particularly, to a hydraulic machine having a confluence
control valve.
BACKGROUND ART
[0002] A variety of machines obtaining power from pressurized fluid
are used in construction sites, industrial fields, and the like.
For example, such machines supply pressurized fluid to actuators,
which in turn work using the pressure of the fluid supplied
thereto.
[0003] In general, hydraulic machines are provided with a plurality
of hydraulic sources, each of which is configured to supply
pressurized fluid to at least one actuator corresponding thereto.
Some hydraulic machines are provided with a confluence control
valve configured to direct pressurized fluid provided by a
hydraulic source corresponding thereto to an actuator corresponding
to another hydraulic source. Accordingly, such hydraulic machines
can supply a sufficient amount of pressurized fluid to two or more
actuators corresponding to another hydraulic source even in the
case in which the two or more actuators are simultaneously
operated.
DISCLOSURE OF INVENTION
Solution to Problem
[0004] According to an aspect, a hydraulic machine may include:
first and second hydraulic sources; a first travel control valve in
fluid communication with the second hydraulic source; a first
attachment control valve in fluid communication with the second
hydraulic source; a confluence control valve in fluid communication
with the first hydraulic source and, in a confluence position,
directing fluid from the first hydraulic source to the first
attachment control valve; a first signal line connected to the
confluence control valve; and a first pilot line connected to the
confluence control valve. When the first travel control valve is in
a non-neutral position and the first attachment control valve is in
a first non-neutral position, first signal pressure may be
generated in the first signal line to move the confluence control
valve to the confluence position. When first pilot pressure is
generated in the first pilot line, the first pilot pressure may
move the confluence control valve to the confluence position.
[0005] The methods and apparatuses of the present disclosure have
other features and advantages that will be apparent from or that
are set forth in greater detail in the accompanying drawings which
are incorporated herein, and in the following Detailed Description,
which together serve to explain certain principles of the present
disclosure.
BRIEF DESCRIPTION OF DRAWINGS
[0006] FIG. 1 is a conceptual view illustrating a structure of a
hydraulic circuit of a hydraulic machine according to exemplary
embodiments;
[0007] FIG. 2 is a conceptual view illustrating a structure of a
hydraulic circuit of a hydraulic machine according to exemplary
embodiments;
[0008] FIG. 3 is a graph illustrating the relationship between a
pressure level in the first signal line and a movement of the
confluence control valve of the hydraulic machine illustrated in
FIG. 2; and
[0009] FIG. 4 is a graph illustrating the relationship between a
pressure level in the first pilot line and a movement of the
confluence control valve of the hydraulic machine illustrated in
FIG. 2.
MODE FOR THE INVENTION
[0010] Hereinafter, reference will be made to the present
disclosure in detail, embodiments of which are illustrated in the
accompanying drawings and described below, so that a person having
ordinary skill in the art to which the present disclosure relates
could easily put the present disclosure into practice.
[0011] FIG. 1 is a conceptual view illustrating a structure of a
hydraulic circuit of a hydraulic machine according to exemplary
embodiments.
[0012] In some embodiments, a hydraulic machine may be a
construction machine, such as an excavator. It should be
understood, however, that the hydraulic machine according to the
present disclosure is not limited to being a construction machine
and may include a variety of machines that carry out a variety of
types of work using power obtained from hydraulic pressure.
[0013] In some embodiments, the hydraulic machine may include a
first hydraulic source 34 and a second hydraulic source 33. The
first hydraulic source 34 and the second hydraulic source 33 may be
hydraulic pumps supplying pressurized fluid.
[0014] In some embodiments, the hydraulic machine may include a
first travel control valve 6 in fluid communication with the second
hydraulic source 33. In some embodiments, the first travel control
valve 6 may be moved between a neutral position and a non-neutral
position. In some of such embodiments, the non-neutral position may
include two non-neutral positions, and thus, the first travel
control valve 6 may be moved between the neutral position and the
two non-neutral positions. In the neutral position, the first
travel control valve 6 may return pressurized fluid from the second
hydraulic source 33 to a tank (not shown) through a tank return
line T1. In the non-neutral position, the first travel control
valve 6 may direct pressurized fluid from the second hydraulic
source 33 to a travel actuator (not shown) while returning fluid
from the travel actuator to the tank through the tank return line
T1. In some embodiments, the travel actuator may be a hydraulic
motor.
[0015] In some embodiments, the hydraulic machine may include a
first attachment control valve 7 in fluid communication with the
second hydraulic source 33. In some embodiments, the first
attachment control valve 7 may be moved between a neutral position
and a first non-neutral position. In some of such embodiments, the
first attachment control valve 7 may be moved between the neutral
position, the first non-neutral position, and a second non-neutral
position. In the neutral position, the first attachment control
valve 7 may return pressurized fluid from the second hydraulic
source 33 to the tank through the tank return line T1. In the first
non-neutral position or the second non-neutral position, the first
attachment control valve 7 may direct pressurized fluid from the
second hydraulic source 33 to an attachment actuator and return
fluid from the attachment actuator to the tank through tank return
line T1. In some embodiments, the attachment actuator may be a
hydraulic cylinder actuating an attachment, such as a boom, an arm,
or a bucket.
[0016] In some embodiments, when the first travel control valve 6
is in the neutral position and the first attachment control valve 7
is in the neutral position, fluid supplied by the second hydraulic
source 33 may return to the tank through the tank return line T1
after sequentially passing through the first travel control valve 6
and the first attachment control valve 7.
[0017] In some embodiments, the hydraulic machine may include a
confluence control valve 3 in fluid communication with the first
hydraulic source 34. In some embodiments, the confluence control
valve 3 may be moved between a neutral position and a confluence
position, a non-neutral position. In the neutral position, the
confluence control valve 3 may return pressurized fluid from the
first hydraulic source 34 to the tank through the tank return line
T1. In the confluence position, the confluence control valve 3 may
direct pressurized fluid from the first hydraulic source 34 to the
first attachment control valve 7 through a line 19.
[0018] In some embodiments, the hydraulic machine may include a
first signal line 28 connected to the confluence control valve 3.
When the first travel control valve 6 is in the non-neutral
position and the first attachment control valve 7 is in the first
non-neutral position, first signal pressure may be generated in the
first signal line 28. The first signal pressure may move the
confluence control valve 3 to the confluence position.
[0019] In some embodiments, the hydraulic machine may include a
first pilot line Pi3 connected to the confluence control valve 3.
When first pilot pressure is generated in the first pilot line Pi3,
the first pilot pressure may move the confluence control valve 3 to
the confluence position.
[0020] In some embodiments, the hydraulic machine may include a
second pilot line a3 and a third pilot line b3 connected to the
first attachment control valve 7. When second pilot pressure is
generated in the second pilot line a3, the second pilot pressure
may move the first attachment control valve 7 to the second
non-neutral position. In some embodiments, the second pilot line a3
and the first pilot line Pi3 may in fluid communication with each
other. When third pilot pressure is generated in the third pilot
line b3, the third pilot pressure may move the first attachment
control valve 7 to the first non-neutral position.
[0021] In some embodiments, the third pilot line b3 and the first
pilot line Pi3 may in fluid communication with each other. In some
embodiments, a check valve may be provided between the second and
third pilot lines a3 and b3 and the first pilot line Pi3 to only
allow a one-directional flow from the second and third pilot lines
a3 and b3 to the first pilot line Pi3.
[0022] In some embodiments, the hydraulic machine may include a
first drain line Dr4.
[0023] When the first attachment control valve 7 is in the neutral
position, the first signal line 28 may be in fluid communication
with the first drain line Dr4 through the first attachment control
valve 7, so that the first signal pressure may not be generated in
the first signal line 28. In some embodiments, when the first
attachment control valve 7 is in the first non-neutral position, a
flow of fluid from the first signal line 28 to the first drain line
Dr4 may be blocked. In some of such embodiments, when the first
attachment control valve 7 is in the first non-neutral position, a
flow of fluid from the first drain line Dr4 to the first signal
line 28 may be allowed. When the first attachment control valve 7
is in the second non-neutral position, the first signal line 28 may
communicate with the first drain line Dr4 through the first
attachment control valve 7, so that the first signal pressure may
not be generated in the first signal line 28.
[0024] In some embodiments, the hydraulic machine may include an
auxiliary valve 22, a second signal line 13, and a second drain
line Dr2. When the auxiliary valve 22 is in an open position, the
first signal line 28 may be in fluid communication with the second
drain line Dr2 through the auxiliary valve 22, so that the first
signal pressure may not be generated in the first signal line 28.
When the first travel control valve 6 is in the non-neutral
position, second signal pressure may be generated in the second
signal line 13 to move the auxiliary valve 22 to a closed position.
In some embodiments, the hydraulic machine may include a third
drain line Dr3. When the first travel control valve 6 is in the
neutral position, the second signal line 13 may be in fluid
communication with the third drain line Dr3 through the first
travel control valve 6, so that the second signal pressure may not
be generated in the second signal line 13.
[0025] In some embodiments, the hydraulic machine may include a
pilot pressure supply 35.
[0026] A portion of fluid supplied by the pilot pressure supply 35
may flow to the tank through a line 25, the second signal line 13,
the first travel control valve 6, and the third drain line Dr3. In
addition, a portion of fluid supplied by the pilot pressure supply
35 may flow to the tank through the line 25, the first signal line
28, the first attachment control valve 7, and the first drain line
Dr4. In some embodiments, the pilot pressure supply 35 may be a
hydraulic pump.
[0027] In some embodiments, the hydraulic machine may include a
fourth drain line Dr1 connected to the confluence control valve
3.
[0028] Since fluid flowing through the tank return line T1 may
basically flow at a large flow rate, and the tank return line T1
may be provided with a non-return function, backpressure may be
generated against the fluid flowing through the tank return line
T1. When the first signal line 28 and the second signal line 13 are
configured to be in fluid communication with the tank return line
T1, backpressure may cause a variety of sensors to malfunction and,
even in the case in which at least one of the first travel control
valve 6 and the first attachment control valve 7 is in the neutral
position, may accidently move the confluence control valve 3.
Accordingly, as described above, some embodiments of the prevent
disclosure may be configured such that the first signal line 28 and
the second signal line 13 in fluid communication with the first
drain line Dr4, the second drain line Dr2, and the third drain line
Dr3, instead of being in fluid communication with the tank return
line T1, thereby removing the problem that would otherwise be
caused by the backpressure in the tank return line T1.
[0029] FIG. 2 is a conceptual view illustrating a structure of a
hydraulic circuit of a hydraulic machine according to exemplary
embodiments.
[0030] In some embodiments, the hydraulic machine may include a
third hydraulic source 32, a second travel control valve 5 and a
second attachment control valve 4, the second travel control valve
5 and the second attachment control valve 4 in fluid communication
with the third hydraulic source 32.
[0031] In some embodiments, when a first attachment control valve 7
and the second attachment control valve 4 are in neutral positions,
fluid in a first signal line 28 may flow to a first drain line Dr4
through the second attachment control valve 4 and the first
attachment control valve 7. When the first attachment control valve
7 is in a first non-neutral position and/or the second attachment
control valve 4 is in a third non-neutral position, fluid
communication between the first signal line 28 and the first drain
line Dr4 may be blocked.
[0032] In some embodiments, when a first travel control valve 6 is
in a neutral position and the second travel control valve 5 is in a
neutral position, fluid in a second signal line 13 may flow to a
third drain line Dr3 through the second travel control valve 5 and
the first travel control valve 6. When the first travel control
valve 6 is in a non-neutral position and/or the second travel
control valve 5 is in a non-neutral position, second signal
pressure may be generated in the second signal line 13 to move an
auxiliary valve 22 to a closed position.
[0033] In some embodiments, the hydraulic machine may include pilot
lines a7 and b7 connected to the second attachment control valve 4.
When pilot pressure is generated in the pilot line a7 or b7, the
pilot pressure may move the second attachment control valve 4 to a
non-neutral position. In some embodiments, the pilot lines a7 and
b7 may be in fluid communication with a first pilot line Pi3. In
some of such embodiments, a check valve may be provided between the
pilot lines a7 and b7 and the first pilot line Pi3 to only allow a
one-directional flow from the pilot lines a7 and b7 to the first
pilot line Pi3.
[0034] In some embodiments, the hydraulic machine may include a
third attachment control valve 8 in fluid communication with a
second hydraulic source 33. When the first attachment control valve
7, the second attachment control valve 4, and the third attachment
control valve 8 are in neutral positions, fluid in the first signal
line 28 may flow to the first drain line Dr4 through the second
attachment control valve 4, the first attachment control valve 7,
and the third attachment control valve 8. When the third attachment
control valve 8 is in a non-neutral position, fluid communication
between the first signal line 28 and the first drain line Dr4 may
be blocked. In some embodiments, the non-neutral position may
include two non-neutral positions.
[0035] When the first travel control valve 6 is moved to the
non-neutral position in response to pilot pressure being generated
in a pilot line a4 or a pilot line b4 and/or the second travel
control valve 5 is moved to the non-neutral position in response to
pilot pressure being generated in a pilot line a5 or a pilot line
b5, a flow of fluid to the third drain line Dr3 may be blocked, so
that second signal pressure is generated in the second signal line
13, thereby moving the auxiliary valve 22 to a closed position. In
the closed position of the auxiliary valve 22, when pilot pressure
is applied to at least one of the pilot line b3, the pilot line a7,
and a pilot line a2 or b2, at least one corresponding attachment
control valve, among the attachment control valves 7, 4, and 8, may
be moved to a non-neutral position. Here, first signal pressure may
be generated in the first signal line 28 to move the confluence
control valve 3 to a confluence position. In contrast, even in the
case in which pilot pressure is generated in at least one of the
pilot line a3 and the pilot line b7, fluid may be drained through
the first drain line Dr4, so that the first signal pressure is not
generated.
[0036] FIG. 3 is a graph illustrating the relationship between a
pressure level in the first signal line 28 and a movement of the
confluence control valve 3 of the hydraulic machine illustrated in
FIG. 2, while FIG. 4 is a graph illustrating the relationship
between a pressure level in the first pilot line Pi3 and a movement
of the confluence control valve 3 of the hydraulic machine
illustrated in FIG. 2.
[0037] Pressure in the first signal line 28 is illustrated as
rapidly increasing at once, thereby moving the confluence control
valve 3 to a confluence position. This may consequently apply an
impact to an attachment corresponding to the third attachment
control valve 8. In contrast, pressure in the first pilot line Pi3
may relatively gradually increase depending on the movement of an
input device (e.g. an joystick) by an operator, so that no impact
is applied to the attachment.
* * * * *